Avoid overflow in WebRtcSpl_DotProductWithScale

webrtc/common_audio/signal_processing/dot_product_with_scale.c

-/*
- *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
-
-int32_t WebRtcSpl_DotProductWithScale(const int16_t* vector1,
-                                      const int16_t* vector2,
-                                      size_t length,
-                                      int scaling) {
-  int32_t sum = 0;
-  size_t i = 0;
-
-  /* Unroll the loop to improve performance. */
-  for (i = 0; i + 3 < length; i += 4) {
-    sum += (vector1[i + 0] * vector2[i + 0]) >> scaling;
-    sum += (vector1[i + 1] * vector2[i + 1]) >> scaling;
-    sum += (vector1[i + 2] * vector2[i + 2]) >> scaling;
-    sum += (vector1[i + 3] * vector2[i + 3]) >> scaling;
-  }
-  for (; i < length; i++) {
-    sum += (vector1[i] * vector2[i]) >> scaling;
-  }
-
-  return sum;
-}